Quantitative Data Flashcards
Give three general features of quantitative research
- Is generally scientific in nature
- Is based upon proving a hypothesis
- Takes a positivist approach
Give the 5 elements of the hierarchy of evidence
- Systematic reviews
- Clinical trials
- Observational studies
- Case reports
- Opinions or ideas
Describe a randomised control trial
A drug or treatment is tested against a placebo using a group of subjects. Typically those who receive the effective drug are randomly selected to ensure objectivity.
Describe single, double and triple blinding in randomised controlled trials.
Single: patient is not aware of the treatment being received
Double: patient and researcher are not aware of the treatment being received
Triple: patient, researcher and data analysers are not aware of the treatment being received
Describe a cohort study
Groups of people demonstrating defining characteristics will be studied (typically for a period of time). Groups typically experience a common event collectively.
Describe a case control method of data collection
Case control studies compare groups of individuals generally comparing one group who demonstrate certain characteristics to another group who do not. Aims to identify a relationship between a risk factor and disease prevention.
Define the difference between a hypothesis and a null hypothesis:
A hypothesis predicts the possibility of something taking place, whereas a null hypothesis predicts the possibility of something not taking place.
How may bias occur within surveys taken as a part of quantitative data collection (give three answers)
- insufficient sample size
- slow response rate of participants
- poor analysis of data and data findings
Give two types of survey in relation to time
- longitudinal (surveys are taken at regular intervals over a long period of time)
- cross sectional (surveys are undertaken at a single point in time)
Name 5 methods of data collection in quantitative research
- Closed ended questionairres
- Closed ended interviews
- Experiments
- Clinical trials
- Surveys
What does quantitative research begin with?
A hypothesis or a null hypothesis.
Which type of data is used within quantitative research?
Numerical figures or statistics.
What is the basis of knowing within quantitative research?
Quantitative research examines the cause and effect relationship between variables involved in research.
Is the researcher involvement within quantitative research subjective or objective?
The researcher takes an objective approach within quantitative research to ensure that data is not obscured by bias.
How do quantitative research studies control the influence of extraneous variables?
By conducting their studies in a controlled lab environment.
What is the theoretical focus of quantitative research? Inductive or deductive? Why?
Quantitative research takes a deductive approach because it focuses on the hypothesis established and aims to save time and reduce wastage of resources available.
What are the two types of data analysis used in quantitative research?
- Descriptive- aims to highlight the data gathered without drawing a conclusion.
- Inferential- aims to use the data to draw assumptions and reach a conclusion.
Are quantitative research findings generalisable?
YES.
What are the three types of quantitative research design?
- Experimental- uses manipulation and controlled testing to understand processes. Participants are randomly assigned. Has a control group and an intervention.
- Quasi-experimental- an independant variable is manipulated without the random assignment of participants. Aims to evaluate interventions without random allocation of participants.
- Descriptive/non-experimental- A group of subjects whom cannot be manipulated by the experimenter. No control group, intervention or randomisation.
What is a systematic review?
A systematic review assesses and evaluates all research that analyses a particular clinical issue. Only data which matches criteria is included in the review which ensures relevancy.
Name the ‘gold standard’ experimental design within quantitative research.
Randomised control trials- include a randomised sample, a control group and an intervention. Each participant has an equal chance of receiving the intervention which helps to eradicate bias.
A cohort study is a descriptive, non experimental study. Describe what takes place in a cohort study.
A cohort study examines a group of individuals who demonstrate defining characteristics, For example- a group who have undergone a particular event together. The group is then studied for a period of time.
A case control study is a descriptive, non experimental study. Describe what takes place in a case control study.
Identifies participants who demonstrate an outcome of interest and a group of control patients who do not display this outcome of interest. The groups are compared and the aim is to establish a risk factor leading to disease.
An observational study is a descriptive, non experimental study. Describe what takes place in an observational study.
A study which observes anything that can be effectively measure such as differences in size, shape colour etc.
A survey is a descriptive, non experimental study. Describe what takes place in a survey.
Survey’s use questionairres, interviews and alternative data collection tools. They can be longitudinal (take place over a long period of time) or cross sectional (data collected at one period of time only). They seek to find variables which can be related to one another.
What is meant by probability sampling within quantitative research?
The likelyhood of a person being selected within the sample is known. Researchers want to identify a representative sample from which to collect data so that the data can be generalised. In order to achieve this generalisability, all elements in the target population much have an equal chance of being selected.
What is meant by non-probability sampling in quantitative research?
The likelihood of a person or event being selected is unknown. It is therefore unknown whether the sample can be used to represent a larger portion of the population.
What does a p value of LESS than 0.05 suggest?
A p value of less than 0.05 would suggest that there is a significant difference from what was predicted within the null hypothesis. Therefore the null hypothesis can be rejected. The alternative hypothesis will be used instead.
What does a p value of MORE than 0.05 suggest?
A p value of more than 0.05 would suggest that there is not a significant enough difference against the null hypothesis to reject it. Therefore the null hypothesis is accepted.
Define validity within research.
Validity is the extent to which the results of the study are likely to represent what they intend to. I.e. whether the results measure what they are supposed to measure.
Define external validity within research.
Can the results of the research be generalised to the wider population?
Define internal validity within research.
Are there any factors which are likely to of affected the research whilst it was taking place i.e. external variables. NOTE: within quantitative research, studies typically take place within a controlled environment which reduce the likelihood of results being effected by external variables.
Define reliability within research.
Reliability is the likelihood of the results being the same if the research analysis were to be repeated multiple times.
What is the relationship between reliability and validity within research?
Results can be reliable (i.e. they can be repeated and produce the same data) but not valid (i.e. they can not be generalised to the wider population or represent fact).
What does a confidence interval indicate?
The range of values which are likely to include the specified population. A 95% confidence interval states that there is a 95% chance that the results collected will include the population needed.
Why is it important to include confidence intervals within research?
They help to indicate clinical significance when results are not statistically significant.
How do we define statistical significance within research?
By establishing a P value. The smaller the P value the more significant the research and the more likely a hypothesis is to be rejected.
What is the difference between descriptive and inferential statistics?
Descriptive statistics describe what can be directly observed within data sets. I.e. what the data demonstrates. Inferential statistics make assumptions about the data collected about a particular population.
What does PARIHS stand for in relation to clinical research and practice?
Promoting Action (on) Research Implementation (in) Health Services
What is most likely to reduce the likelihood of successfully implementing research findings into practice?
Failing to identify appropriate stakeholders
What are the 4 levels of measurement?
N- nominal
O- ordinal
I- interval
R- ratio
Which type of hypothesis testing corresponds to nominal data?
Chi-squared
Which type of hypothesis testing corresponds to ordinal data?
Spearmans correlation
Which type of hypothesis testing corresponds to interval and ratio data?
Pearsons correlation
Inferential statistics are used to determine (exam question answer)…
The statistical significance of any observed differences between groups.
Which types of data are parametric?
Normally distributed interval or ratio data.
Which types of data are non-parametric?
Non normally distributed interval or ratio data as well as nominal and ordinal data.
